This invention relates to mechanical face seals and to metal bellows for use therein.
A mechanical face seal generally comprises a rotary seal element and a stationary seal element usually in the form of rings in rubbing or running face-to-face sealing contact, the rotary seal ring surrounding and be secured directly or indirectly to a rotary element such, for example, as a rotary shaft and the stationary seal ring also surrounding the rotary shaft but being secured against rotation to a stationary element such, for example, as a housing within-which the shaft rotates.
One of the seal elements is movable axially of the shaft and means is provided between the housing and same to urge it into contact with the other seal element to provide the necessary sealing effect and to compensate for wear which occurs through use in the running faces of the seal rings.
The urging means may be a mechanical spring or a metal bellows, either stationary or rotatable depending upon which sealing element it is associated with, and the present invention is concerned with a mechanical face seal incorporating a metal bellows as the means for applying axial pressure and with the construction of the metal bellows per se.
The use of metal bellows in mechanical face seals has been known for many years and in various forms such, for example, as discs (washers) welded together at alternate inner and outer diameters, or a metal tube rolled or otherwise formed into corrugated or convoluted configuration.
The mechanical face seal of this invention is concerned with a metal bellows of the latter construction.
The mechanical face seal of the present invention employs a metal bellows whereof the crowns of the corrugations or convolutions have inner and outer radii of the same dimension.